Noise filter comprising a monolithic laminated ceramic varistor

Abstract

A noise filter of a monolithic type in which a common electrode is formed in a sintered body having varistor characteristics so as to extend from a first portion to a second portion of side surfaces of the sintered body, and at least one through electrode is formed in a position at a height spaced apart from the common electrode through a sintered body layer in the direction of thickness so as to extend from a third portion to a fourth portion of the side surfaces of the sintered body and to intersect the common electrode.

What is claimed is: 
     
       1. A noise filter comprising: a monolithic cofired multilayer sintered body comprising a plurality of laminated ceramic layers having varistor characteristics and a set of electrodes separated by said layers;   said sintered body having a pair of main surfaces which define a direction of thickness therebetween, and an outside surface extending between said main surfaces;   said set of electrodes comprising:   a common electrode formed in the sintered body so as to extend from a first portion to a second portion of said outside surface of the sintered body; and   at least one through electrode spaced apart from said common electrode by at least one ceramic layer in the direction of thickness and extending from a third portion to a fourth portion of the outside surface of said sintered body and crossing said common electrode.   
     
     
       2. The noise filter according to claim 1, wherein a plurality of said through electrodes are formed. 
     
     
       3. The noise filter according to claim 2, wherein said through electrodes adjacent to each other are formed in positions at different heights in the sintered body. 
     
     
       4. The noise filter according to claim 2, wherein said plurality of through electrodes are arranged in a distributed manner on sintered body layers positioned on both sides of the common electrode. 
     
     
       5. The noise filter according to claim 4, wherein the adjacent through electrodes are formed in positions at different heights. 
     
     
       6. The noise filter according to claim 1, wherein said through electrode is constituted by a plurality of through electrode portions overlapped with each other separated by a sintered body layer. 
     
     
       7. The noise filter according to claim 1, wherein a plurality of said common electrodes are formed. 
     
     
       8. The noise filter according to claim 1, wherein the first and second portions of the outside surfaces of said sintered body are a pair of side surfaces opposed to each other of the sintered body, and the third and fourth portions thereof are another pair of side surfaces opposed to each other of the sintered body.